In an industrial field of mobile phones and the like, there is used a device that notifies of an incoming call and the like, by way of a vibration; and as such a device, there is proposed a linear actuator in which a movable element equipped with a permanent magnet is provided to a stator, wherein the linear actuator is activated by a coil (refer to Patent Document 1 and Patent Document 2). Using such a linear actuator makes it possible to change an intensity level and a frequency of vibration, with a driving signal to be supplied to the coil.